This invention relates to a fuel preheating system for use with internal combustion engines. The invention is best adapted to use with conventional engines using fuel injection, but may also be used with diesel engines.
In any internal combustion engine, fuel is vaporized and mixed with air for combustion. It is known that preheating gasoline or other fuel for internal combustion engines can produce more efficient vaporization and higher combustion efficiency and engine performance than cold fuel. However, preheating the fuel is often not practical because of other problems which may result, such as vapor lock.
Using heat from the engine to preheat the fuel is known. In Canadian patent no. 1,225,888 (Edward L. Nave), for example, a "vapor carburetor" is described, in which a baffled, insulated fuel reservoir holding approximately one litre of fuel is provided. Hot water from the engine block is passed through the fuel reservoir via copper tubing or the like, to preheat the fuel. Air is also drawn into the reservoir to form a fuel/air mixture.
Neither the Nave device nor any other prior art devices known to the inventors provides careful control over the temperature of the fuel, which the inventors have found to be critical to optimum performance.